Firearm for firing caseless ammunition

ABSTRACT

A FIREARM FOR FIRING CASELESS AMMUNITION IS PRESENTED IN WHICH THE CASELESS OR COMBUSTIBLE CASED CARTRIDGE IS NOT INTRODUCED INTO THE BARREL AT ITS BREECH END, BUT IS INTRODUCED INTO EITHER THE MUZZLE OF THE BARREL OR AT SOME POINT ALONG THE BARREL WHERE THE PRESSURES EXERTED UPON THE BARREL WHEN THE CARTRIDGE IS FIRED WILL BE LOWER THAN THOSE EXERTED UPON THE BREECH PORTION OF THE BARREL.

Oct. 12, 1971 w, OR 3,611,612

FIREARM FOR FIRING CASELESS AMMUNITION Filed July 15, 1968 m A22 Jig. E

PRESSURE BEHIND THE PROJECTILE 3/ lll llllllllll DISTANCE OF PROJECTILE TRAVEL INVEN TOR.

United States Patent 3,611,612 FIREARM FOR FIRING CASELESS AMMUNITION Michael W. York, 1200 S. Arlington Ridge Road 507, Arlington, Va. 22202 Filed July 15, 1968, Ser. No. 744,765 Int. Cl. F410 21/00; F41]? 17/02 US. CI. 4276 Claims ABSTRACT OF THE DISCLOSURE A firearm for firing caseless ammunition is presented in which the caseless or combustible cased cartridge is not introduced into the barrel at its breech end, but is introduced into either the muzzle of the barrel or at some point along the barrel where the pressures exerted upon the barrel when the cartridge is fired will be lower than those exerted upon the breech portion of the barrel.

This invention relates to a firearm for firing caseless or combustible cased ammunition in which the ammunition is not introduced into the barrel at the breech end of the barrel. This invention allows the use of a barrel whose breech end is sealed or closed both during firing and loading of the ammunition. This firearm is useful in reducing or eliminating the breech sealing problems associated with present firearms that fire caseless or combustible cased ammunition.

The desirability of firearms that fire caseless or combustible cased ammunition is well known. At the present time normal firearms use a case that is usually made of metal or some plastic. This case serves the purpose of containing the propellant and also the purpose of sealing the breech end of the barrel of the firearm when it is fired to prevent the escape of powder gases at the breech end of the firearm barrel. In spite of the current need for such a case it adds extra weight to the ammunition and adds to the cost of manufacture of ammunition, In addition, the present ammunition casings remain after firing and must be ejected from the firearm and disposed of in some manner.

Various attempts have been made to eliminate these commonly used metallic or plastic casings. Some of these attempts are described in the June 1968 edition of Guns, Vol. XIV, No. 806 in an article beginning on page 18.

The primary problem associated with eliminating the cartridge casings is a means of sealing the breech end of the firearm barrel. One such means is described in U.S. Pat. 3,354,780. However, all these prior art means are located at or near the breech end of the firearm barrel where they are subjected to the maximum or near maximum pressures developed when cartridges are fired. This means that severe problems are encountered in sealing such breeches particularly against gas pressures from about 30,000 pounds per square inch to some 70,000 pounds per square inch or above this that are present in firing modern high power normal loads and the so-called wildcat loads.

It has now been discovered that many improvements over these prior art means are possible by the firearm of this invention.

Accordingly, an object of this invention is to provide a firearm that reduces the problems of sealing the barrel when firing caseless ammunition.

Another object of this invention is to provide a firearm that is capable of firing caseless or combustible cased ammunition that produces high breech pressures.

A further object of this present invention is to provide a firearm that allows the breech end of the barrel to be sealed both during loading and firing of the firearm.

Other objects and features of novelty of this invention "ice will be specifically pointed out or will become apparent when referring, for a better understanding, to the following description taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a cross sectional view of one embodiment of the firearm of this invention;

FIG. 2 is a partial cross sectional view of another embodiment of the firearm of this invention; and

FIG. 3 is a graph showing the pressure behind the projectile versus the distance of projectile travel down the bore of a firearm as the firearm is fired.

Referring now in greater detail there is shown in FIG. 1 a cross section of one embodiment of the firearm of this invention wherein this firearm has a unitary or undivided barrel 1 having a closed breech end that fits within tubular member 2. This barrel has an elongated open port 4 whose long axis is substantially parallel to the long axis of the barrel extending completely through a portion of the side wall of the barrel for receiving caseless or combustible cased ammunition 21, a means 10 for igniting this ammunition, a freebored or smoothbore section 7, and a section having rifling indicated by reference numeral 6. The tubular member 2 has a port 3 for receiving caseless or combustible cased ammunition 21. The tubular member 2 also has a slot 9 that allows a handle 8 that is fixed to the barrel 1 to move backward and forward. The tubular member 2 also contains a spring 5 that tends to push the barrel 1 in a forward direction or in a direction out of the tubular member 2.

FIG. 2 shows a cross sectional view of another embodiment of the firearm of this invention that incorporates the same basic parts as the embodiment shown in FIG. 1. However, the barrel 1 and tubular member 2 do not have ports 4 and 3 for receiving caseless or combustible cased ammunition 21. The firearm shown in FIG. 2 also has several additional parts. There is a magazine or clip 22 that holds combustible cased or caseless ammunition 21, and a member 23 attaching the magazine or clip 22 to the tubular member 2. A push rod is also illustrated by reference numeral 24. The barrel 1 also incorporates a leaf spring 25 for catching and securing the caseless or combustible cased ammunition 21.

FIG. 3 is a graph showing pressure behind the projectile versus the distance a .projectile travels down the bore of a firearm as the firearm is fired. The abscissa indicates projectile travel and the ordinate indicates pressure behind the projectile. No units are shown, but the tick marks 31 are intended to indicate any arbitrary unit of distance of travel such as inches and the tick marks 32 are intended to indicate any arbitrary units of pressure such as pounds per square inch. On the pressure behind the projectile versus projectile travel curve 30, reference numeral 33 indicates maximum pressure and reference numeral 34 indicates the pressure behind the projectile at the muzzle of the firearm.

The firearm of this invention functions in the following manner. In the embodiment shown in FIG. 1 the handle 8 is pulled to the rear until ports 3 and 4 are aligned. A caseless or combustible case round of ammunition 21 is then inserted into the barrel through ports 3 and 4. This insertion can be either manual or by some mechanical means such as a clip 22. The barrel 1 is then permitted to move and slide forward within the tubular member 2 under the force exerted by the spring 5. This forward movement with a suitable caseless or combustible cased round of ammunition 21 will result in the caseless round 21 being forced to the rear of the barrel 1 and against the igniting means 10 due to the inertia of the caseless round 21. The caseless round 21 is then fired by the igniting means 10 and through other means that are familiar to those skilled in the art.

When the caseless round 21 is fired pressure is developed that is exerted both against the breech end of the barrel 1 and against the base of the projectile of the caseless round 21. This pressure builds up at various speeds depending upon the type of propellent that is used. Normally this pressure reaches a maximum point indicated by reference numeral 33 before the projectile has moved down any major portion of the barrel 1. The spring and the inertia of the barrel 1 hold the barrel in its forward position during this build up of pressure. As the projectile continues its movement along the barrel 1 the pressure against the projectile and also against the walls of the barrel 1 drops as indicated in FIG. 3.

With the proper selection of spring 5 tension, propellent, projectile, barrel 1 weight, and tolerances which are easily determined by those skilled in the art, the projectile does not reach port 4 until the pressures against the walls of the barrel 1 and the base of the projectile are considerably reduced over the peak pressure 33 indicated in FIG. 3. This means that any sealing means at the port 4 is exposed to a much lesser pressure than any means located at the breech end of the barrel 1.

With the proper selection of propellents and projectiles and a proper fitting of the barrel 1 into tubular member 2 by those familiar to the art, the tubular member 2 that is located on the exterior of the barrel can be sufficient itself for sealing the barrel 1. It is necessary that the port 4 of this invention be located at a distance forward of the breech end of the barrel that is beyond the projectile travel points corresponding to reference numeral 33, the peak pressure, and rearward of the muzzle of the barrel and thus prior to the travel point corresponding to reference numeral 34, the pressure behind the projectile at the muzzle of the firearm, in FIG. 3 in the embodiment represented in FIG. 1.

The selection of this distance of the port 4 from the breech will depend upon the type of caseless or combustible cased ammunition 21 that is to be used in the firearm of this invention. Once a choice of propellent and projectile is made, the location of the port 4 can be easily determined by those skilled in the art. Generally, a fast burning propellent and heavier projectile means that the port 4 can be located closer to the breech end of the barrel 1. Whereas, a slower burning propellent and a lighter projectile require that the port 4 be located at a point more distant from the breech end of the barrel 1.

The embodiment shown in FIG. 2 functions in a manner similar to that of the embodiment shown in FIG. 1, except that the caseless ammunition 21 is fed into the muzzle of the barrel 1 rather than through a port 4. To operate this embodiment of the firearm of this invention, the handle 8 is pulled to the rearward position as it is shown in FIG. 2. The barrel 1 is then released by any means familiar to those skilled in the art. The barrel 1 then moves in a forward direction indicated by arrow A. In doing this the barrel strips a caseless round of ammunition 21 from the clip or magazine 22.

In some instances, the inertia effects of the caseless round of ammunition 21 will be sufiicient to seat the caseless round of ammunition 21 against the ignition means 10 so that the caseless round 21 is held in place by the leaf spring 25. In some cases additional positive means of seating the caseless round of ammunition 21 such as the push rod 24 will be desirable. Such means will be particularly desirable with lightweight caseless rounds of ammunition 21. Various means will be apparent to those skilled in the art removing such means as the push rod 24 from the path of the projectile prior to firing the caseless ammunition 21. Such means can be easily activated by the forward movement of the barrel 1.

The caseless or combustible case ammunition 21 for which the firearm of this invention is designed in that similar to the type described in the June l9 68 is.sue of Guns in an article starting on page 18 and in US, Pat. 3,345,945 and US. Pat. 3,311,057. The firearm of this invention can be made capable of manual, automatic, or semi-automatic firing by means that are well known in the art and can be attached to or adapted to a variety of different mountings and stocks. v v

Although the invention has been described in considerable detail with reference to certain preferred .embodiments, it will be understood that variations and modifications may be made Within the spirit and scope of the invention as defined in the appended claims.

What is claimed is: p

1. A firearm for firing caseless or combustible cased ammunition comprising an undivided barrel having a closed breech end, said barrel having an elongated open port whose long axis is substantially parallel to the long axis of the barrel extending completely through a portion of the side wall of said barrel that is adapted to receive said caseless or combustible cased ammunition, said port being located forward of the breech end of said barrel at a location along said barrel rearward of the muzzle of said barrel where said port will be exposed to pressures that are lower than the maximum pressures developed in said barrel against the base of the projectile of said ammunition when said firearm is fired, and means for sealing propellant gases in said barrel at said port.

2. The firearm as recited in claim 1 wherein said means for sealing propellant gases in said barrel comprises a sealing member located on the exterior of said barrel.

3. The firearm as recited in claim 2 wherein said barrel has both rifled and smooth bore sections.

4. The firearm as recited in claim 2 including igniting means located in said barrel for igniting said caseless or combustible cased ammunition.

5. The firearm as recited in claim 2 wherein said barrel and said sealing member are adapted to permit slideable movement between said barrel and said sealing member.

6. The firearm as recited in claim 5 wherein said sealing member comprises a tubular member adapted to surround said port.

7. The firearm as recited in claim 6 wherein said tubular member is sealed at one end and slips over and permits movement of said barrel within said tubular member.

8. The firearm as recited in claim 7 wherein said sealed tubular member has a port adapted to receive said caseless or combustible cased ammunition.

9. The firearm as recited in claim 7 including a spring for assisting forward movement of said barrel within said sealed tubular member.

10. The firearm as recited in claim 7 including a handle fixed to said barrel to assist the manual movement of said barrel within said sealed tubular member.

References Cited UNITED STATES PATENTS 14,253 2/1856 Robertson et a1 42-10 2,363,675 11/ 1944 Johnson 4251 X 2,427,035 9/1947 Wilcoxon 891.35 2,830,497 4/1958 'Smoot et al. 89--1.806 1,994,490 3/1935 Skinner 891.3 UX

FOREIGN PATENTS 869,271 5/ 1961 Great Britain.

BENJAMlN A. BORCHELT, Primary Examiner S. C. BENTLEY, Assistant Examiner US. Cl. X.R. 

